franke



(No Model.) 3 Sheets-Sheet 1.

ELECTRIC CLOCK SYSTEM. A

110. 549,715. Patented 111011.v 12, 1895.

ANDREW B GRAHAM. PHOTG-UTMUWASHINGTON. D C

No Model.) 3 sheets-Sheet 2.

` A. FRANKE. ELECTRIC CLOCK SYSTEM.

No. 549,715lv Patented Nov. 12, 1895.

:o rames.

AN DREW EGRANAM. PHOTQvLrmO WASHN ETEN. n C

UNITED STAT-Es PATENT OFFICE.

ADOLF FRANKE, OF BERLIN, GERMANY.

ELECTRIC-CLOCK SYSTEM.

SPECIFICATION forming part of Letters Patent No. 549,715, dated November12, 1895.

Application iiled September 19, 1893. Serial No. 485,850. (No model.)Patented in Germany March 7, 1893, No. 73,850; in SwitzerlandAugust 12,1393,1To. 6,978; in England August 14,1893,No.15,450; in Norway August17,1893,No. 3,362;

in Belgium August 19,1893,N0. 106,030; in France August 21, 1893, No.232,285,

XXVIII, 34,703, LXVIII, 123.

and in Italy September 30, 1893,

To @ZZ whom, it may concern:

Beit known that 1, ADoLF FEANKE, doctor of philosophy, a subject of theKing of Prussia, Emperor of Germany, residing at Berlin, in the Kingdomof Prussia, German Empire, have invented new and useful Improvements inor Relating to the Regulation of Clocks from a Central Clock-Station,(for which I have obtained patents in Switzerland August 12,1893,No. G,978; in Norway August 17, 1893, No. 3,362; in France August 21, 1893,No. 232,285; in Belgium August 19, 1893, No. 106,030 5 in Italy, Reg.Gen., Vol. XXVIII, No. 34,703, Reg. Att., Vol. LXVIII, No. 123,September 30, 1893; in England August 14, 1893, No. 15,450, and inGermany March 7, 1893, No. 7 3,850,) of which the following is aspecication.

My invention has reference to a system for synchronizing a series ofclocks from a primary or master clock; and it consists, essentially, incombining with a master-clock a series of secondary clocks provided withcircuitclosers operated by the individual secondary clocks for closingthe circuit to throw the synchronizing-magnet of said clocks into actionin succession, so that the hand-setting mechanism of only one clock at atime is synchronized, and consequently a comparatively weak battery canbe used for the purpose of synchronizing. I also provide means at thecentral station for indicating or recording' the times of closing andbreaking the circuit for the purpose of detecting possibleirregularities of action in the system.

The nature of my said invention will best be understood when describedin connection with the accompanying drawings, in which- Figure 1 is adiagrammatic view of a clock system'embodying my invention. Fig. 2 is asectional elevation of a device for actuating the synchronizing orhand-setting devices. Fig. 3 is an enlarged detail view of the same.Fig. 4is a face view, on an enlarged scale, illustrating theconstruction of the hand-setting mechanism. Figs. 5 and 6 are face viewsof detail parts.

Similar letters and numerals of reference designate corresponding parts.

Referring at present to Fig. 1, the letter WV designates the rotarycontact-disk at the central station, which, in conjunction with thespring-contact c, closes the circuit of battery B-one pole .of which isgrounded-at predetermined regular intervals. In this example I haveassumed forty clocks 1 2 3, &c., included in the system, which are to besuccessively synchronized, and have assumed two hours for completesynchronization of the system. Consequently said circ uit-closer isconstructed to close the circuit every three minutes. The disk WV mayform an operative part of the master-clock, or it maybe actuated in anyother suitable manner. The shaft of the disk is electrically connectedby a brush CZ with the main wire 10, and from the latter are conductedthe several branch wires 11 12, dac. to the secondary clocks.

Each secondary clock is provided with a complete time-keeping movement,which actuates the disk or cam of a circuit-closer c to close thecircuit at predetermined intervals (in this instance every two hours)and just before the circuit is closed at the circuit-closer IV c of thecentral station. The circuit thus closed through the individual clockpasses through an electro magnetic device e, which throws thehand-setting device into operation. Shortly after synchronization thecircuit is again broken. The clocks are thus synchronized in successionand not simultaneously, as heretofore, and a comparatively weak batterywill answer.

The circuit-closing and hand-setting devices may be of any well-knownconstruction. I have herein shown a peculiar device for the purpose ofactuating the hand-setting devices, the construction of which I willpresently describe. y In order to determine if the secondary clocksarebeing properly synchronized, a suitable recording device Risinterpolated in the main wire 10 at the central station. This may be anywell-known register containing an electromagnet c', operating anarmature-lever t', carrying a style arranged to mark upon a tape t, fedin usual manner. The tape may be a time-strip, or a second style may-beused phere.

to indicate the time on the tape. If an impression is missing or foundmisplaced, failure of the corresponding secondary clock to act or to actat the proper time is indicated. Knowing the time at which each clock issynchronized, the attendant perceives from the recording device whichclock is not operating properly. If desired, any ordinary galvanoscopemay be substituted for the register which will indicate to the attendantthe closing of the circuit.

It is of course to be understood that the synchronizing mechanism of thesecondary clocks can be caused to operate upon the interruption of thecircuit at the master-clock instead of at the time of closing the same.As usual, the circuit is first closed at the masterclock and then at thecorresponding secondary clock.

In Figs. 2 and 3 I have shown a device for operating the hand-settingmechanism, the same consisting of a solenoid m, connected at one endwith the shaft of the d'isk of the circuit-closer a by a brush b, Fig.l, and having its opposite end grounded. The solenoid m contains asoft-iron core q, having a conical end fitted to a valve-seat o of afitting, to which are attached an inlet-pipe Z for water under pressure,an inlet-pipe p for air, and a discharge-pipe z for the water. Vhen thesolenoid m is vitalized, the valve-core q is lifted from its seat o andthe water passes throug'h pipes l z and causes air to be drawn from theair-conduit. Vh'en the solenoid is devitalized, the water is shut olfand atmospheric air enters the air-pipe p. By the variations in pressurethe hand-setting devices are operated. The power thus obtained issufficient not only to set the clocks, but also to wind the clocks, andseveral hand-setters may be connected to one air-pipe when the clocksare in the same building.

I will now describe the construction of the hand-setting mechanism usedin combination with the pneumatic operating device shown in Fig. 2,reference being had to Fig. 4. Referring to said figure, the letter Adesignates a casing divided into an upper and lower compartment by avery iiexible leather diaphragm B. The upper compartment is connectedwith the ejector (shown in Fig. 2) by the pipe p. The lower compartmentis open to the atmos- The diaphragm B is connected by a rod S with alever H, which can turn about the winding-post of the clock-movement C.On said lever is mounted an arm provided at its end with a pin s, whichengages with the pivoted bifurcated hand-setting lever G. Said lever isadapted to engage with an arm g, secured to the arbor of the minute-handin the usual manner. On the lever H is also mounted a pawl K, adapted toengage with the ratchet-wheel K', rigidly mounted on the winding-post ofthe movement.. On the arbor of the minute-hand is also mounted a cam a',which, in connection with the contact-arm a,

forms a circuit-closer for the electromagnet or solenoid m', Fig. 2. Therod S is subjected to the action of the spring F, tending to force itdownwardly. The operation is now as follows When the circuit at a a isclosed, the valve q of the ejector is lifted and the air in the uppercompartment of the casing A is partially eX- hausted. The rod S/ islifted, carrying with it the lever H and the parts thereto appertaining,the same then being in the positions shown by full lines in Fig. 4. Vhenthe contact at a a is broken, valve q, Fig. 2, falls and atmospheric airenters through pipes s and p into the upper compartment of casing A andrestores the equilibrium. By virtue of the spring F the rod S is forceddownwardly and the pin s carries the hand-setting lever G intoengagement with the arm g and sets the hands to the correct time. Oncontinued motion of the rod S/ the lever G is released and assumes itsnormal position, while the pawl K engages the ratchet-wheel K and windsup the spring of the movement to such an extent as to bring it back tothe condition of the prior period of synchronization.

If the closing of the circuit at a a is not to take place hourly, but atintervals of several hours, notched disks, such as j j', may be placedon the minute-arbor in position to be engaged by the contact-arm a,which disks permit said arm to fall only when it is oppo site one of thenotches therein.

I am aware that heretofore clock systems have been adopted in which thesecondary clocks were simultaneously synchronized and that such clockswere synchronized by self-contained circuit closers thrown into ac-vtion before or upon the closing of the circuit at the master-clock, andtherefore I do not claim this as my invention.

IVhat I claim as new isl. In a clock system, the combination with amaster clock provided with a circuit closer, of a series of secondaryclocks provided with hand-setting devices and with circuit closersoperated to close and break the circuit at predetermined intervals, andtimed to throw the clocks successively at predetermined intervals intothe circuit of the master clock, a source of electricity, and electricalconnections, substantially as described.

2. In a clock system, the combination with a Amaster clock provided witha circuit closer, of a series of secondary clocks provided withhand-setting devices and with circuit closcrs operated to close andbreak the circuit at predetermined intervals, and timed to throw theclocks successively at predetermined intervals into the circuit of themaster clock, a registering or recording device in the circuit of themaster clock, a source of electricity, and electrical connections,substantially as described.

3. The combination withasecondary clock, of a pneumatic synchronizingmechanism rio 1o handsetter, and an operative connection between thehand-setter and the diaphragm, substantially as described.

In testimony whereof I have signed my name to this speciiication in thepresence of tWo subscribing Witnesses.

ADOLF FRANKE. Vitnesses:

LUDWIG GLASER, GUSTAV HLSMANN.

